In other words, don’t expect Snohomish County government to return to normal — at least not right away.

The criminal probe began in October after county social worker Tami Dutton went to County Councilman Dave Somers to report trysting with Reardon during the executive’s business trips. Dutton has known Reardon, who is married with two children, since they attended Mariner High School in the 1980s. She said their affair had been ongoing for six years. She believed he improperly spent taxpayer money during their travels.

Somers relayed the allegations to Snohomish County Prosecuting Attorney Mark Roe. To avoid a conflict of interest, Roe asked the State Patrol to investigate and for Island County Prosecuting Attorney Greg Banks to make a charging decision. Like Reardon, Somers, Roe and Banks are all Democrats.

Banks announced Wednesday that the State Patrol investigators turned up insufficient evidence to charge Reardon with any crime. That news took some pressure off Reardon.

On the same day, however, the State Public Disclosure Commission confirmed that it is investigating Reardon’s campaign activities. The PDC received a complaint about Reardon in February after The Herald reported on public records that show the executive made extensive use of government resources in his political campaign. The commission, which enforces elections laws statewide, suspended active follow-up by staff until the patrol completed its investigation, PDC spokeswoman Lori Anderson said.

The state’s inquiry is likely to take several months. It’s up to the commission’s staff to decide whether to recommend civil charges. If they do, the commission will schedule an enforcement hearing.

The PDC has the authority to levy steep fines and may increase penalties for people who have had previous run-ins over campaign issues. That happened to Reardon a year ago, when PDC commissioners fined him $750, with $500 of the amount suspended, for failing to report that outside groups paid for business trips in 2009 to the United Arab Emirates and Washington, D.C.

County code and state law also allow people to bring ethics complaints, or petition for recall, when they believe an elected official has engaged in misconduct. No ethics complaints or recall petitions are pending against Reardon.

Snohomish County GOP chairman Bill Cooper said the party has no plans to initiate a recall, which in Washington must identify specific wrongdoing in office and receive a judge’s OK before any petition signatures are gathered.

Relations between Reardon and the county’s other elected leaders have been strained for years, but the investigation has made that worse.

In February, the County Council asked Reardon to take paid administrative leave while the investigation was being conducted. Reardon responded by releasing a video that made it clear he wasn’t going anywhere.

Some members of the council even considered starting their own parallel investigation of Reardon, Sullivan said, though a brief conservation with county attorneys convinced them otherwise. Under the county charter, the council has the authority to subpoena witnesses while investigating legislative issues.

Sullivan called that power “subpoena lite,” because the council, unlike Congress, has no enforcement arm and would have to get a court’s assistance in rounding up any witnesses who refused to cooperate.

“No (Snohomish) County Council has ever issued a subpoena, so we’d be stumbling over ourselves trying to figure out how to get one done,” he said.

Reardon’s attorney, John Wolfe of Seattle, said Reardon is the victim of a conspiracy carried out by politicians and members of the news media.

In a statement on Wednesday, Wolfe declared Reardon “exonerated” and described the investigation as “a thinly disguised and improper effort by Mr. Reardon’s political adversaries to undermine the electoral will of the people.”

Wolfe noted that Reardon’s election opponent from last year, state Rep. Mike Hope, R-Lake Stevens, works as a Seattle police officer. Word of the probe became public days before the election after a potential witness who had been approached by patrol detectives contacted Hope.

Neither Wolfe nor Reardon responded to emails Thursday pressing for more details about how others allegedly conspired against Reardon.

The lone Republican on the County Council, John Koster, found it impossible to believe that Democratic leaders, such as Roe and Somers, would have targeted Reardon and found detectives and others willing to play along.

“The State Patrol and the prosecutor obviously thought there was some merit to do this investigation,” Koster said. “They obviously thought this was more than political hype.”

Reardon for months has kept a low profile, though he has recently begun speaking again at public events. He’s offered no direct comment on the investigation, or Banks’ decision, other than his attorney’s statement.